Resonant Band Hybridization in Alloyed Transition Metal Dichalcogenide Heterobilayers.

Autor: Catanzaro A; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK., Genco A; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.; Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci, 32, Milano, 20133, Italy., Louca C; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.; Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci, 32, Milano, 20133, Italy., Ruiz-Tijerina DA; Departamento de Física Química, Instituto de Física, Universidad Nacional Autónoma de México, Ciudad de México, C.P., 04510, Mexico, México., Gillard DJ; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK., Sortino L; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.; Chair in Hybrid Nanosystems, Nanoinstitute Munich, Faculty of Physics, Ludwig-Maximilians-Universität München, 80539, Munich, Germany., Kozikov A; Department of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, UK.; School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK., Alexeev EM; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.; Cambridge Graphene Centre, University of Cambridge, 9 J. J. Thomson Avenue, Cambridge, CB3 0FA, UK., Pisoni R; Solid State Physics Laboratory, ETH Zurich, Zurich, CH-8093, Switzerland., Hague L; National Graphene Institute, University of Manchester, Manchester, M13 9PL, UK., Watanabe K; Research Center for Electronic and Optical Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan., Taniguchi T; Research Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan., Ensslin K; Solid State Physics Laboratory, ETH Zurich, Zurich, CH-8093, Switzerland., Novoselov KS; Institute for Functional Intelligent Materials, National University of Singapore, Singapore, 117546, Singapore., Fal'ko V; Department of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, UK.; Henry Royce Institute for Advanced Materials, University of Manchester, Manchester, M13 9PL, United Kingdom., Tartakovskii AI; Department of Physics and Astronomy, The University of Sheffield, Sheffield, S3 7RH, UK.
Jazyk: angličtina
Zdroj: Advanced materials (Deerfield Beach, Fla.) [Adv Mater] 2024 May; Vol. 36 (19), pp. e2309644. Date of Electronic Publication: 2024 Feb 13.
DOI: 10.1002/adma.202309644
Abstrakt: Bandstructure engineering using alloying is widely utilized for achieving optimized performance in modern semiconductor devices. While alloying has been studied in monolayer transition metal dichalcogenides, its application in van der Waals heterostructures built from atomically thin layers is largely unexplored. Here, heterobilayers made from monolayers of WSe 2 (or MoSe 2 ) and Mo x W 1 - x Se 2 alloy are fabricated and nontrivial tuning of the resultant bandstructure is observed as a function of concentration x. This evolution is monitored by measuring the energy of photoluminescence (PL) of the interlayer exciton (IX) composed of an electron and hole residing in different monolayers. In Mo x W 1 - x Se 2 /WSe 2 , a strong IX energy shift of ≈100 meV is observed for x varied from 1 to 0.6. However, for x < 0.6 this shift saturates and the IX PL energy asymptotically approaches that of the indirect bandgap in bilayer WSe 2 . This observation is theoretically interpreted as the strong variation of the conduction band K valley for x > 0.6, with IX PL arising from the K - K transition, while for x < 0.6, the bandstructure hybridization becomes prevalent leading to the dominating momentum-indirect K - Q transition. This bandstructure hybridization is accompanied with strong modification of IX PL dynamics and nonlinear exciton properties. This work provides foundation for bandstructure engineering in van der Waals heterostructures highlighting the importance of hybridization effects and opening a way to devices with accurately tailored electronic properties.
(© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)
Databáze: MEDLINE
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